1. Field of the Invention
The present invention relates to beverage dispensers and, more particularly, but not by way of limitation, to a beverage dispenser with an improved component configuration which increases both beverage dispensing capacity and the quantity of beverages dispensed at a temperature below the industry standard of 42.degree. F.
2. Description of the Related Art
The rental or purchase of commercial real estate suitable for the operation of food and drink service establishments is extremely expensive, especially in large metropolitan areas. Consequently, available space must be utilized with maximum efficiency, particularly countertop space which provides the service area for customers as well as additional customer seating. Thus, beverage dispensers which typically reside on countertops must be compact to occupy the least amount of countertop space.
Although beverage dispenser size is important, the principal beverage dispenser criteria remains beverage dispensing capacity. That is, beverage dispensers must dispense beverages at a temperature below the 42.degree. F. industry standard while still satisfying customer demand. Unfortunately, beverage dispensers capable of serving high volumes typically are bulky and occupy large amounts of countertop space.
Conversely, compact beverage dispensers rarely have drink dispensing capacities sufficient to serve large numbers of customers. Therefore, any beverage dispenser design must balance size and compactness against drink dispensing capacity. Accordingly, the primary objective in the design of beverage dispensers is to decrease their size while increasing or at least maintaining their current beverage dispensing capacity.
U.S. Pat. No. 3,892,335 issued Jul. 1, 1975 to Schroeder discloses an early beverage dispenser design which attempts to combine compactness with increased beverage dispensing capacity. The beverage dispenser of U.S. Pat. No. 3,892,335 includes a housing which defines a cooling chamber containing a cooling fluid. A refrigeration unit which resides over the cooling chamber includes an evaporator coil extending into the cooling chamber. Product and water lines which are surrounded by the evaporator coil reside within the center of the cooling chamber. The product and water lines communicate with a product and water source, respectively, to deliver the product and water, which is typically carbonated water, to beverage dispensing valves.
In operation, the refrigeration unit cools the cooling fluid so that the cooling fluid freezes in a slab about the evaporator coil. An agitator motor drives an impeller via a shaft to circulate unfrozen cooling fluid about the cooling chamber. That circulation provides the heat exchange between the product and water lines and the cooling fluid because, as the unfrozen cooling fluid circulates, it receives heat from the product and water lines and delivers that heat to the frozen cooling fluid slab. As a result, the frozen cooling fluid melts to dissipate the heat from the product and water so that a cold beverage is dispensed from the dispensing valves.
Proper circulation requires a steady flow of the unfrozen cooling fluid from underneath the frozen cooling fluid slab, around its sides, over its top, and back through its center. Circulation of the unfrozen cooling fluid along the above-described path is essential to the heat exchange process which produces cool drinks and increases beverage dispensing capacity. Unfortunately, the placement of the water and product lines in the center of the cooling chamber reduces the circulation of unfrozen cooling fluid about the product and water lines and the frozen cooling fluid slab. That is, the product and water lines prevent the unfrozen cooling fluid from flowing through the center of the frozen cooling fluid slab which severely limits the contact between the frozen and unfrozen cooling fluid. Consequently, the beverage dispenser disclosed in U.S. Pat. No. 3,892,335 fails to provide maximum heat exchange between the product and water and the cooling fluid which results in a diminished beverage dispensing capacity.
U.S. Pat. No. 4,916,910 issued Apr. 17, 1990 to Schroeder discloses a beverage dispenser which moves the product and water lines from within the evaporator coil to a position on the bottom of the cooling chamber underneath the evaporator coil. That position change allows the height of the evaporator coil to be reduced which provides the beverage dispenser with a low profile. Unfortunately, although the size of the beverage dispenser has been decreased, the problem of increasing the heat exchange between the cooling fluid and product and water has not been solved.
Maximum heat exchange from the product and water to the cooling fluid occurs when the unfrozen cooling fluid contacts the frozen cooling fluid slab over a maximum surface area. In the beverage dispenser of U.S. Pat. No. 4,916,910, the compressed evaporator coil completely freezes the cooling fluid above the product and water lines all the way to the edges of the cooling chamber so that no circulation of unfrozen cooling fluid about the frozen cooling fluid slab occurs. Consequently, insufficient heat exchange develops because the unfrozen cooling fluid only contacts the bottom of the frozen cooling fluid slab. Accordingly, heat exchange is diminished because the area of contact between the unfrozen cooling fluid and the frozen cooling fluid slab has been minimized.
Accordingly, a beverage dispenser design which occupies a minimum of countertop space while permitting the contact between the unfrozen cooling fluid and the frozen cooling fluid slab to occur along a maximum surface area to provide maximum heat exchange, thereby increasing drink dispensing capacity, is highly desirable.